Question

I’m trying to post some very simple data to a php file using jquery and then get the json response but I seem to be running into a road block somewhere. Here is my jquery:

<script>
    $(function() {
        $('.resend-verify').click( function() {
            var userid = $(this).attr('rel');            
            $.ajax({
                type: "POST",
                url: "resend_verification.php",
                contentType: "application/json; charset=utf-8",
                data: "userid=" + userid,
                dataType: "json",
                success: function(data) {
                    console.log(data.response);
                    if(data.response == 'error') {
                        $('div.alert').addClass('error');
                    }
                    $('div.alert').html(data.comment);
                }

            });

        });       
    });
</script>

and here is the php page it posts to

<?php

if ($_SERVER['REQUEST_METHOD'] == "POST") { // Check For Post
    require '../../config.php'; // Site Settings
    require '../../connectors/mysqlConnector.php';
    include $DIR['php'] . 'functions.php'; // Common Functions

    //var_dump(json_decode($_POST));
    $UserID = $_POST['userid'];

    $userSQL = "SELECT p.user_firstname,p.user_lastname,a.user_email,a.user_salt FROM web_profiles p INNER JOIN web_accounts a ON p.user_id = a.user_id WHERE p.user_id ='" . $UserID . "'";
    $userQuery = mysql_query($userSQL);
    //var_dump($userSQL);
    $user = mysql_fetch_object($userQuery);

    if (!$user->user_email) {
        $response = array('response' => 'error', 'comment' => 'User not found');
    } else {
        // Send User Verification Email
        $sendmail = new sendMail();
        $message = createUserAuthEmail($user->user_firstname, $user->user_lastname, $user->user_salt, $Site['register_email_body']);

        $content['body'] = '<br /><br />' . $message . '<br /><br />DO NOT REPLY TO THIS EMAIL! IT IS ONLY AN AUTOMATED NOTIFICATION EMAIL!';
        $sendmail->set(to, $user->user_email);
        $sendmail->set(subject, 'Action Required to Activate Membership');
        $sendmail->set(from, '[e-mail]');
        $sendmail->set(html, true);
        $sendmail->getParams($content);
        $sendmail->parseBody();
        $sendmail->setHeaders();
        if ($sendmail->send()) {
            $response = array('response' => 'success', 'comment' => 'email sent');
        } else {
            $response = array('response' => 'error', 'comment' => 'Error sending email');
        }
    }
    echo json_encode($response);
}
?>

The problem im having is that if I use contentType: “application/json; charset=utf-8” the $_POST is always empty. And when I remove contentType: “application/json; charset=utf-8” the $_POST is populated but I cant get a json response. What am I doing wrong??

Answer 1

You should read through the jquery documentation once more, especially the part that covers the data and dataType parameters. data must be a key/value object, i.e.:

data: { 'userid': userid }

…and for dataType, allowed values are xml, html, text, json, and jsonp. If your PHP script sends a suitable Content-type header (e.g. header('Content-type: text/json');, then you can simply leave this parameter at the default (‘Intelligent guess’). jQuery will infer the response type from its content type header. You should send the header anyway because otherwise, the server will probably assume you’re sending HTML and add a HTML content type header itself, which jQuery then chokes on.
It’s probably also a good idea to set the internal encoding and output encoding in your PHP script, so that it understands the request correctly and sends a well-formed UTF-8 response.

For further debugging, you might want to:

• add some logging code to your PHP, for example, dump the $_POST array and the response you’re sending to a text file on the server
• post a test request to your PHP script using something like curl or wget, and see if the response is what you expect
• have your javascript post to a dummy script that does nothing but log the request and send an empty response; see if that works
• step through your javascript using a script debugger (e.g. Firebug on Firefox, or the thing that’s built into Chrom[e|ium]); set a breakpoint inside the success handler and see if it’s hit, and if so, what the response contains